A three mile stretch of the B1397 and A152 between Gosberton and Sutterton is set to be resurfaced later this month.
Work is due to start of Monday, September 18 and is expected to last for around 14 days.
The B1397 will be closed between Gosberton and the A17 throughout.
A short section of the A152 will also need to be closed for three days at the start of the project and then again for a few days towards the end.
During the improvements, traffic will be directed to use the A152, A52, A17 and A16 in order to get around the closure.
Councillor Richard Davies, in charge of highways at Lincolnshire County Council, said: “These roads have suffered a lot of wear and tear over the years so it’s essential we repair them to ensure the route remains safe for people to use.
“This will be one of the biggest resurfacing jobs we’ve done this year, and will significantly improve things for motorists.
“As with any road improvements, there is likely to be some short-term disruption, so we recommend people leave additional time for their journeys and take alternative routes where possible.”